Treatment of textile materials



Patented May 16, 1939 UNITED STATES PATENT OFFICE TREATRIENT OF TEXTILE MATERIALS No Drawing.

rial No. 2,204.

Claims.

This invention relates to improvements in the treatment of textile materials whether cellulosic or non-cellulosic, fibres, yarns, or fabrics, such for example, as those of linen, cotton or regenerated cellulose.

According to the invention, such materials are subjected to a swelling, or swelling and shrinking, process or to a plurality of such processes, consecutive or not, after they have been impregnated with an insolubilisable substance which has then been insolubilised in the material; such impregnation may, for example, be effected by the use of a soluble body of suitably small molecular weight, whose solution has a low viscosity, or a mixture of bodies, which body or mixture is then converted to a solid product in the textile material. Solutions of resin components or of liquid or solid intermediate condensation products may be initially used.

The object of the treatment according to the invention is to improve the tensile strength and ripping strength and durability and/or other textile properties.

The invention further consists in treating such materials, containing an insoluble resin, with a soap or other suitable washing solution, so that the fabrics will wet out readily. treating the materials with a. swelling and shrinking agent after which they may either be washed and dried and subjected to textile finishing processes, or they may be impregnated with further quantities of synthetic resin forming components which are afterwards insolubilised and if desired, again subject'ed to the swelling process.

For example, a linen fabric (dyed or otherwise) may be impregnated by one of the methods described in U. S. Patent No. 1,734.516 with synthetic resin forming components which are subsequently insolubilised. The treated material is now thoroughly washed oiT so as to obtain a good subsequent swelling action and is then treated with a swelling agent such as caustic soda of mercerising strength, preferably allowing shrinkage to take place in both length and width. The

fabric is then washed, to remove the caustic soda and dried. It is found that not only has the fabric the crease-resisting properties known to be produced by such resin treatment, but the handle of the fabric strength, durability and the draping and other textile properties are improved compared with those of a resin treated fabric that has not been subjected to such swelling treatment.

In the prior patent mentioned above, it has already been proposed to mercerise or swell 9.

Application January 17, 1935, Se-

In Great Britain January 25,

cotton fabric with the object of making the material more receptive to the action of the impregnating agent. In the present process, however, a fabric already containing an insoluble synthetic resin is treated with a swelling agent with the object of improving its textile properties, leaving the necessary amount of resin in the fabric. I

The invention may be carried out on resin impregnated materials having crease-resisting properties for improving their textile properties or it now becomes possible to give further treatment to materials which have already received a resin impregnation treatment so that it is possible to incorporate further quantities of resin in the fabric. The invention is, however, not limited to the improvement of materials possessing crease-resisting properties since it is applicable to the treatment of any yarn or fabric which contains a synthetic resin whether it possesses crease-resisting properties or not. Thus, we may treat a material containing a quantity of resin too small to produce a crease-resisting effect.

Before treatment with the swelling agent, it is desirable to subject the fabr'c to a preparatory treatment. Some effect can be obtained by spraying the fabric with water and allowing it to stand for some hours before treatment with the swelling agent but we prefer to treat the fabric by washing it with an alkaline solution which preferably contains a wetting agent.

If desired, the action of someswelling agents such as caustic soda may be increased-by warming the solution, e. g., to 40 C.

The invention will now be described by an illustrative example dealing with the treatment of a linen fabric but it must be understood that the invention is not limited to this example since other fabrics can be treated and other strengths of solutions and other resins and other swelling agents can be used. In this example, the impregnating agent is a urea formaldehyde resin, but other insolubilisable impregnating agents can be used. The particular swelling agent in this example is caustic soda, but other swelling agents can be used, for example, caustic potash or caustic soda in conjunction with carbon bisulphide. The preliminary wash is at 80 C. for two to three minutes but other temperatures and times may be used.

The'swelling agent must be capable of producing a marked swelling action on the composite material (fabric plus resin) and the action must be substantially greater than that exerted by water alone when applied in the usual manner.

The order of magnitude of the swelling power should be similar to that exerted by the usual swelling agents such as caustic alkali.

The swelling may be produced by mixtures of compatible swelling agents or these agents in alternation with or without intermediate washing or by the application of incompatible swelling agents in alternation (e. g., acid-alkali) with or without intermediate washing.

The swelling may also be produced in known ways by a combination of agents which singly do not produce swelling but which jointly simultaneously or in alternation produce the desired effect.

When treating a resin which is resistant to acid such as phenol formaldehyde resin, acid swelling agents may be used. An acid swelling agent can be used on fabrics containing a urea formaldehyde resin but in general, the swelling agent should no exert too great a solvent action on the resin in its condensed form.

The swelling may be performed at room temperature, or at lower or higher temperatures if desired.

Example 1 50 parts by weight of urea are dissolved in 100 parts by weight of (neutralised) 40% formaldehyde solution. This solution is boiled under a reflux condenser with 3% of aqueous ammonia (sp. gr. .880) calculated on the total weight of the solution for 3 minutes and then cooled rapidly. The solution is diluted with water to say 50% to 10% strength and 1% by weight (on the diluted solution) of tartaric acid is added.

A bleached and mercerised and, if necessary, dyed linen fabric finished to 36-38" wide, after washing and drying, is well impregnated with the above solution which is then well squeezed so that the fabric contains sufliclent weight of liquor to give the required result. The fabric is then dried to say 38-40" wide at a temperature below 100 C. and afterwards heated to 170 C. for two to three minutes. (The process is not limited to heating at a high temperature as in some cases much lower temperatures can be used.) It is then washed for 4 minutes at C. in an aqueous solution containing as wetting agent an alkali salt of a sulphonated fatty alcohol /r% and soda ash A%. The fabric is then squeezed off and without drying run into a bath of caustic soda 50 to 63 Tw. without tension for three minutes or more when it shrinks both in the warp and weft. It is' then run through a mercerising machine, containing caustic soda of usual mercerising strength, with tension, quickly washed off with warm water, soured in acetic acid solution, washed off, dried and finished to 34-36".

Example 2 A solution is prepared as in Example 1. It is diluted to 50 or 55% of its original concentration, and 0.7 gm. tartaric acid added to each c. c. of diluted reaction mixture.

Thin mercerised cotton fabric is impregnated with this liquid, thoroughly squeezed to remove as much surplus liquor as possible, dried at a relatively low temperaturepreferably below 100 0., and is then heated for 2 to 3 minutes at C. It is then washed for a few minutes at 80 C. in an aqueous solution containing of an alkali salt of a sulphonated fatty alcohol, or other suitable wetting agent, and of soda ash. The fabric is then squeezed and passed through caustic soda solution of mercerising strength with or without tension, washed and finished in any suitable manner, preferably with a small shrinkage of about 1 to 2% in both warp and weft.

Example 3 Fabric made from regenerated cellulose or from a mixture of cotton and regenerated cellulose can be treated in the same way as in Example 2, but in this case a rather larger shrinkage is an advantage, and either caustic soda or caustic potash may be used for the swelling and shrinking agent.

Example 4 100 gm. cresol, 200 c. c. formalin (40% by volume formaldehyde solution) and 0.8 gm. caustic potash dissolved in a little water are mixed together and boiled under a reflux condenser for 5 minutes. After being quickly cooled a further 0.8 gm. caustic potash is added. An absorbent cotton fabric is impregnated with this solution, which has been previously diluted with an equal volume of water containing 4% olein (Turkey red oil). The fabric is nipped (squeezed) so as to remove as much surface liquor as possible, dried at a low temperature, preferably below 100 C., and is then heated for 2 to 3 minutes at 170 C. It is then immersed for 2 minutes at 80 C. in an aqueous solution containing soda ash, and sulphonated fatty alcohol alkali salt, or other suitable wetting agent, and again squeezed and dried. It is then immersed in a solution of sulphuric acid (108 Tw.) till the necessary swelling and shrinkage is obtained, washed and finished as in the previous examples.

The swelling treatment improves the strength and durability and other textile properties.

Thus in the treatment of linen, if the resistance to wear (durability) is measured on a fabric which has been impregnated with resin, and on another fabric which has then been subjected to the swelling and shrinking treatment, it is found that the resistance to wear can be increased many fold.

The tensile strength is also increased. Two illustrative comparisons may be given.

Fabric made crease-resistant by impregnation with synthetic resin and washed- Pounds Linen.-Tensile strength 17.3 After swelling and shrinking (12%) 31.4 Cotton.-Washed crease-resistant fabric"- 53.8 After swelling and shrinking (4%) 61.9

, losic textile material containing within the fibres an insolubilised synthetic resin which comprises subjecting the material to a swelling treatment with a mercerizing agent.

2. Process of treating a cellulosic textile fabric containing within the fibres an insolubilised synthetic resin which consists in washing the fabric with an alkaline solution of a wetting agent and then swelling the material with a mercerizing agent.

3. Process of treating a cellulosic textile material containing within the fibres an insolubilised synthetic resin which consists in subjecting the material to a preparatory treatment [adapted 5 to facilitate the action of a swelling agent, and then swelling and shrinking with a mercerizing agent the prepared material to increase its strength or durability.

4. A process as in claim 3, in which linen is 10 treated.

5. Process of treating a cellulosic textile material containing within the fibres an insolubilised synthetic resin which comprises subjecting the' material to a swelling treatment with a mer- 15 cerizing agent and shrinking it in both the warp and the weft.

6. Process of treating a cellulosic textile fabric containing within the fibres an insolubilised urea-formaldehyde synthetic resin which com- 20 prises subjecting the material to a swelling treatment with a mercerizing agent.

'If A process as in claim 6,,in which linen is treated.

8. Process of treating linen containing within the fibres an insclubilised synthetic resin which comprises subjecting the material to a swelling treatment with a mercerizing agent.

9. Process of treatinga cellulosic textile fabric containing within the fibres an insolubilised synthetic resin which comprises subjecting the material to a swelling treatment by caustic alkali.

510., Crease-resisting linen containing within the fibres an insolubilised synthetic resin, which linen has been swollen by a mercerizing agent after the insolubilization so as to increase the resistance of the fabric to wear to many times the resistance of the unswollen crease-resisting material.

HARRY CORTEEN. ROBINSON PERCY FOUIDS. FREDERICK CHARLES WOOD. 

